Conventional switched reluctance motors are provided with a rotary position encoder that monitors the position and speed of the rotor. The rotary position encoder is mounted on the motor shaft and typically disposed in proximity to a printed circuit board that controls the motor. The printed circuit board has conventionally been mounted on top of the motor with the motor shaft extending through an opening in the printed circuit board. A drawback of the configuration is that the printed circuit board acts as a barrier to airflow which could otherwise be used to cool the motor and its associated electronic components, including the printed circuit board itself.
The present invention discloses a motor construction having an improved airflow path that overcomes the problems found in the prior art in a convenient and cost-efficient manner.